This study analyzes all patients who presented with acute orbital fractures at Northwestern Memorial Hospital confirmed on radiological imaging and analyzes the incidence of subjective diplopia, abnormal ocular motility exam, and radiographic evidence of entrapment.

Methods

The Enterprise Database Warehouse (EDW) was used to abstract patient records from Northwestern Memorial Hospital (NMH) and Northwestern Medical Faculty Foundation (NMFF) electronic medical records using ICD9 codes for facial fractures or CPT codes for orbital fracture repair. The medical records and radiologic imaging of these patients were reviewed to determine anatomical location of fractures, radiographic evidence of muscle entrapment, and evidence of ocular injury. After review of medical records, certain patients were excluded due to lack of information in the electronic medical record.

Results

Review of CT imaging of facial fractures identified 446 patients with an acute orbital fracture between 2005 and 2011. Of the 446 patients identified, 412 patients had medical records available for review, with two patients having two independent incidents with acute orbital fractures. Of 414 individual incidents analyzed, 52 (13%) of orbital fractures showed radiographic evidence of entrapment and an additional 30 (7%) with possible entrapment indicated by fat but not muscle herniating in the defect or deviation of muscle towards but not through the fracture. A total of 288 (70%) patients reported no diplopia, 56 (13%) patients reported diplopia, and 69 (17%) patient charts did not document the presence or absence of diplopia. Of 56 patients with subjective diplopia, 17 (30%) had evidence of entrapment on CT scan and 5 (9%) patients had possible entrapment. Of 72 patients with restriction of extraocular movements on exam, 24 (33%) had evidence of entrapment on CT scan and 4 (6%) had possible entrapment.

Conclusions

CT imaging is a useful tool for identifying orbital fractures and may be helpful identifying muscle entrapment. 13% of orbital fractures had radiographic evidence of entrapment, 13% had diplopia, and 17% had restriction of eye movements. 52% of patients with radiographic evidence of entrapment had either diplopia or restriction on clinical exam compared to 17% of patients with no evidence of entrapment.